rslogix500 compile issue

hello all. maybe somebody has encountered this before and can lend a hand. i am trying to make offline changes to a program in rslogix500 and when i go to compile it i get the error "Program could not be compiled!Decompiler - > I-code did not verify compile". never seen this one before. any help?

Make sure the Results window is displayed "View/Results or Alt+1". If the program will not Verify it should tell you why there.